Synthesis and biological activity of an acyclic analogue of 5,6,7,8-tetrahydrofolic acid, N-[4-[[3-(2,4-diamino-1,6-dihydro-6-oxo-5- pyrimidinyl)propyl]amino]-benzoyl]-L-glutamic acid.
The synthesis and biological evaluation of N-[4-[[3-(2,4-diamino-1,6-dihydro-6-oxo-5-pyrimidinyl)propyl]amino]- benzoyl]-L-glutamic acid (1) (5-DACTHF, 543U76), an acyclic analogue of 5,6,7,8-tetrahydrofolic acid (THFA), are described. The key intermediate, hemiaminal 8, was prepared in four stages from 3-chloropropionaldehyde diethyl acetal. Reaction of 8 with dimethyl N-(4-aminobenzoyl)-L-glutamate gave the 2,4-bis(acetylamino) derivative 11, which was hydrolyzed with 1 N sodium hydroxide to give 1; the glycine analogue 16 was prepared in a similar manner. The N-methyl analogue 2 and N-formyl analogue 3 were prepared from 11 and 1, respectively. Compounds 1-3 inhibited growth of Detroit 98 and L cells in cell culture, with IC50s ranging from 2 to 0.018 microM. Cell culture toxicity reversal studies and enzyme inhibition tests showed that 1 was cytotoxic but not by the mechanism of the dihydrofolate reductase inhibitor aminopterin. Compound 1 and its polyglutamylated homologues inhibited glycinamide ribonucleotide transformylase (GAR-TFase) and aminoimidazole ribonucleotide transformylase (AICAR-TFase), the folate-dependent enzymes in de novo purine biosynthesis; and 1 was an effective substrate for mammalian folyl-polyglutamate synthetase. The compound inhibited (IC50 = 20 nM) the conversion of [14C]formate to [14C]-formylglycinamide ribonucleotide by MOLT-4 cells in culture. These data suggest that the site of action of 1 is inhibition of purine de novo biosynthesis. Moderate activity was observed against P388 leukemia in vivo.
Kelley
J L
JL
Wellcome Research Laboratories, Research Triangle Park, North Carolina 27709.
McLean
E W
EW
Cohn
N K
NK
Edelstein
M P
MP
Duch
D S
DS
Smith
G K
GK
Hanlon
M H
MH
Ferone
R
R
D000217:Acyltransferases / Q000037:antagonists & inhibitors; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000138:chemical synthesis* / Q000494:pharmacology; D002460:Cell Line; D055598:Chemical Phenomena; D002621:Chemistry; D005493:Folic Acid Antagonists / Q000138:chemical synthesis* / Q000494:pharmacology; D019877:Hydroxymethyl and Formyl Transferases; D007942:Leukemia, Experimental / Q000188:drug therapy; D051379:Mice; D010453:Peptide Synthases / Q000378:metabolism; D051027:Phosphoribosylaminoimidazolecarboxamide Formyltransferase; D051026:Phosphoribosylglycinamide Formyltransferase; D011687:Purines / Q000378:metabolism; D013329:Structure-Activity Relationship; D013763:Tetrahydrofolates / Q000138:chemical synthesis* / Q000494:pharmacology
D000964:Antimetabolites, Antineoplastic; D005493:Folic Acid Antagonists; D011687:Purines; D013763:Tetrahydrofolates; C062810:N-(4-((3-(2,4-diamino-1,6-dihydro-6-oxo-5-pyrimidinyl)propyl)amino)benzoyl)glutamic acid; D019877:Hydroxymethyl and Formyl Transferases; D051026:Phosphoribosylglycinamide Formyltransferase; D051027:Phosphoribosylaminoimidazolecarboxamide Formyltransferase; D000217:Acyltransferases; D010453:Peptide Synthases; C023103:folylpolyglutamate synthetase